It's hard to define MassiveCraft as one way or another. I focus my work for MassiveCraft totally on the Roleplay department, but to me the right of pvp'ers to engage in warfare without being hampered by roleplay, such as what happens on other servers that identify themselves as Roleplay servers, is a holy right.
MassiveCraft breaks conventional identification because most servers that self identify as roleplay servers are primarily servers that for example say "You cannot attack others without an in game RP reason, and raids must happen in roleplay combat". On MassiveCraft, you don't always need a solid reason to kill someone in the wilderness, the only thing we are very strict about is declaring war. The lore universe is also not so strictly enforced on the survival worlds as it is on say Regalia.
In conclusion, you cannot simply say the server is 50% that and 50% that. The lines blur on multiple levels of the difference between RP and PVP, and then we haven't even considered PVE, Economy, Questing, things that can be defined as a main gameplay style.